Toxicologists study the harmful effects of chemical, physical and biological agents on living organisms by detecting and examining the symptoms, mechanisms and treatments of poisoning (especially the poisoning of people).

Weegy: People are exposed to a whole variety of factors that can either promote good health or be hazardous to health, including the physical living environment. [ [ Modern cities can improve health via their material, service-provision, cultural, and aesthetic attributes.5 They also offer opportunities for cost-effective interventions that can serve many people even if carried out on a small scale. Existing health-promoting infrastructure (e.g., drains and distribution networks for kerosene for cooking) can, in some situations, be upgraded to meet the local health demands. Health hazards and inequities remain, however, and new threats have emerged, but the knowledge and technologies for creating a healthy city are available.6
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Weegy: Career as Hydrologists involves studying the movement, distribution and quality of water that is available on the earth and also below the earth's surface. [ In simple words, hydrology is the 'study of water' - its composition and its effect on living things. Water is the important natural resource. It is the most important resource for survival of living things.
Careers in oceanography as consisting of swimming with marine animals at a marine life park or snorkeling in crystal-clear tropical waters studying coral reefs. In reality, these kinds of jobs are extremely rare and there is intense competition for the few jobs that do exist. Most oceanographers work in fields that use science to solve a particular problem in the ocean.
The students interested in hydrology can take courses in subjects like geology, geophysics, chemistry, engineering science, soil science, forestry, and agricultural engineering and civil engineering. Those who are involved in saltwater preservation projects will need knowledge of oceanography.
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Weegy: Marine food webs play a key role in regulating these ecosystem services but there are important gaps in our knowledge and understanding of these functional roles and the way they might respond to environmental change. [ There is evidence that marine food webs are affected by both 'bottom-up' and 'top-down' processes. However, existing knowledge is much greater for lower trophic levels and associated biophysical factors and it is therefore difficult to understand the role of these processes and how the effects of climate change will cascade through the food web and impact on ecosystem services. 'Top-down' and 'bottom-up' processes are also inherently scale-dependent. Scale-dependence is poorly understood which makes it difficult to quantify the large-scale impacts on ecosystem services of changes at small spatial scales (eg marine conservation zones); and vice versa. How functional diversity affects the way marine food webs regulate ecosystem services is unclear, however there is evidence that a loss of biodiversity can negatively impact on ecosystem functioning and services. ] (More)